<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <input type="text" name="" id="">
    <button>检测</button>
    <script>    
      let btn = document.querySelector('button');
      let inp = document.querySelector('input');

      btn.onclick = function(){
        //   console.log(inp.value.startsWith('我'));
        //   console.log(inp.value.endsWith('我爱'));
        //   console.log(inp.value.includes('蜜雪冰城'));
        //   console.log(inp.value.repeat(10));
      }
      
      

    </script>
</body>
</html>